20971357312 has 128 divisors (see below), whose sum is σ = 46962432000. Its totient is φ = 9279857664.

The previous prime is 20971357273. The next prime is 20971357313. The reversal of 20971357312 is 21375317902.

It is a tau number, because it is divible by the number of its divisors (128).

It is not an unprimeable number, because it can be changed into a prime (20971357313) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2400889 + ... + 2409607.

It is an arithmetic number, because the mean of its divisors is an integer number (366894000).

Almost surely, 2^20971357312 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20971357312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23481216000).

20971357312 is an abundant number, since it is smaller than the sum of its proper divisors (25991074688).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20971357312 is a wasteful number, since it uses less digits than its factorization.

20971357312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8818 (or 8806 counting only the distinct ones).

The product of its (nonzero) digits is 79380, while the sum is 40.

The spelling of 20971357312 in words is "twenty billion, nine hundred seventy-one million, three hundred fifty-seven thousand, three hundred twelve".